The Number.parseInt() method parses a string argument and returns an integer of the specified radix or base.

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Syntax

Number.parseInt(string,[ radix])

Parameters

string

The value to parse. If this argument is not a string, then it is converted to one using the ToString abstract operation. Leading whitespace in this argument is ignored.

radix

An integer between 2 and 36 that represents the radix (the base in mathematical numeral systems) of the string. Be careful — this does not default to 10.

The description below explains in more detail what happens when radix is not provided.

Return value

An integer parsed from the given string. If the radix is smaller than 11, and the first non-whitespace character cannot be converted to a number, NaN is returned.

Description

This method has the same functionality as the global parseInt() function:

Number.parseInt === parseInt; // true

and is part of ECMAScript 2015 (its purpose is modularization of globals). Please see parseInt() for more detail and examples.